Jellyfish glowing in dark

Bioluminescent jellyfish produce their own light using proteins like GFP, seen here in blue hues in the dark.

About this subject

Bioluminescent jellyfish belong to various groups, such as hydromedusae from the class Hydrozoa. Bioluminescence is generated by a chemical reaction between luciferin and luciferase, often involving green fluorescent protein (GFP), which emits blue or green light. Species like Aequorea victoria, found in the North Pacific, are famous for this ability. The light serves to attract prey, confuse predators, or communicate. In the deep sea, where sunlight does not reach, bioluminescence is a crucial adaptation. Over 75% of marine organisms in deep waters produce light. Jellyfish have a complex life cycle, alternating between benthic polyps and pelagic medusae. The venom of some species can be painful, but most bioluminescent ones are harmless to humans.

Frequently Asked Questions

Why do jellyfish glow in the dark?

They glow due to bioluminescence, a chemical reaction that produces light to attract prey, confuse predators, or communicate.

Is the light of a bioluminescent jellyfish dangerous?

No, the light itself is not dangerous. Some species may have toxins, but bioluminescence is harmless.

Where can I see bioluminescent jellyfish?

In seas and oceans worldwide, especially at depths below 200 meters. Some species are more common in the North Pacific.